6.5 G vs 308 Ballistics

[Keep The Change]

So I have a friend that has an AR-15 and a DPMS in 308. He was like me in not being familiar with the Grendel and now that he sees me trying put one together he is becoming interested. Especailly since he reloads some of his stuff.

I keep talking to him about the ballistics and flat shooting nature of the round and I think he is trying to justify building one.

So to help in this I wanted to send him some ballistics charts of the 6.5 Grendel and 308. It would be great if there were comparison charts. But I really want to see velocities, energy, and drop for each out to 1000 yards.

You guys have some good sources for that?
I've tried searching the web but it hasn't been satisfactory at this point.
Thanks,
KTC

[mongoosesnipe]

A lot of it comes down to barrel length the Grendel is able to obtain superior balistics over a 308 in barrels 16 inch and under basically if there is room for the powder to burn the 308 has about fifty percent greater powder capacity that won't easily be over come but let's say the both have 20 inch barrels and the 30 shoots 175 match king at 2600 and the Grendel 123 scenar at 2600 the 308 will have 412 inches of drop at 1000 will be traveling at around 1200 fps and have 560 pounds of energy left the Grendel will have 387 inches of drop be traveling at around 1275 and have 445 pounds of energy with say 2 pounds less gun and half the recoil

Bullet drop and velocity are close short range energy goes to the 308

You can play with all kinds of balistic variables online software just google jbm balistics trajectory and punch in your info

[Keep The Change]

Thanks mongoose, I was finally able to find some charts that showed similar data to what you mention.
The Grendel does surpass the 147g 308 once you get out past 600 yds, which I think is of interest for him. It seems like an obvious choice past 500-600 yds to me. I hope one day I can shoot past that.

[LRRPF52]

For close range, the Grendel's advantage is a lighter gun, and much less recoil, with more than plenty of impact on steel targets, and very low wind deflection. The .308 will have more energy, but you pay in gun weight, recoil, ammunition weight, and for reloaders, it sucks up powder a lot faster on the bench.

The Grendel ruined all my devious plans for a lightweight 16" or 18" .308 Carbine, which I had literally dreamed about since childhood. When I saw that Knight's made the SR-25K back in the 1990's, I thought I was in dreamland, and then the Clinton AWB happened and no more .308 carbine for you, silly freedom-loving soldier.

Once the ban expired, .308 carbines on the AR10-type frame started becoming popular, slowly but surely, and I was well on my way to sourcing the parts, but priority went to long-range guns first, because of the Sniper Competitions I was attending every year. I had been watching the Grendel and 6.8 since around 2003-2004, and finally decided on going the Grendel route after watching the market.

I got on Midway's email notification list, and jumped on an AA barrel/bolt combo as soon as I could. After working with the Grendel for some time, I realized that it would be pointless for me to mess with a .308 carbine from that point forward, and I have owned 5 different AR10's. I still keep the custom .260 Rem AR10 for long-range shooting, but it's a heavier gun more appropriate for prone and bipod shooting off solid supports, while the little 16" Grendel is easy to carry and shoot with from all positions, with minimal recoil.

[Y85]

If memory serves, Jay Guthrie's article in Shooting Times a few months ago did some comparisons of Grendel and 308. Good reading.

[Keep The Change]

Thanks guys for the response. I'll check out the Shooting Times article. LRRPF52, if building a bolt gun what would you suggest considering your experience with different calibers at long range.
338 Lapua isn't an option. Too expensive.

[LRRPF52]

Thanks guys for the response. I'll check out the Shooting Times article. LRRPF52, if building a bolt gun what would you suggest considering your experience with different calibers at long range.
338 Lapua isn't an option. Too expensive.

What ranges do you need to shoot out to, what target sizes, and what do you want to happen when the bullet hits?

7mm RSAUM or 7mm WSM, which is also very expensive, but not as bad as .338 LM
.260 Remington (you can also share bullets with the Grendel)

[bwaites]

What ranges do you need to shoot out to, what target sizes, and what do you want to happen when the bullet hits?

7mm RSAUM or 7mm WSM, which is also very expensive, but not as bad as .338 LM
.260 Remington (you can also share bullets with the Grendel)

or 6.5 Creedmoor. The Remington has the advantage of Lapua brass, though.

7 WSM is a great caliber, but quite a bit more recoil than the 260/6.5 Creedmoor. (And yes, I shoot a 7mm WSM in F Class, but mine weighs 18 pounds, it isn't exactly a hunting gun!)

[mongoosesnipe]

a long range bolt gun depends on your definition of long range

[Variable]

7 WSM is a great caliber, but quite a bit more recoil than the 260/6.5 Creedmoor. (And yes, I shoot a 7mm WSM in F Class, but mine weighs 18 pounds, it isn't exactly a hunting gun!)

Still shooting that mouse cartridge? Get a 7mm RUM like mine ya' Sissy!!! (J/K!)

I'd love to shoot mine more if I could afford it, and if the barrel wouldn't evaporate. I might order a new tube next year and have it nitrided for future use.

[adamjp]

I have a few different rifles for different purposes.

For long range deer and still being able to stalk I run a Ruger No.1B in 300H&H. Easy to hit something out to 600m with a 165gn Nosler launched at 3300fps. Weight is 9lb 12oz with a 3-10x50 Kahles MZ.

For long range pigs on wheatfields I built a 7mm SAUM on a Remington 700 in an AICS. Weight is 14lb with a March 3-24 FFP, but those 168gn Berger Hunting bullets at 3050fps shoot flat and hit hard. If I dope the wind right hits out to 700m on a medium sized pig are realistically possible.

The Creedmoor is not a starter here in Australia as it is surpassed in every way by the 6.5x47 Lapua cartridge. Better brass, more available brass, many reamers available in the custom community. The Creedmoor brass is expensive (more than Lapua), unavailable and only Ruger seems to offer rifles in it. Few gunsmiths have reamers as the Lapua case was first and is generally considered a better product for competition shooting. It makes a great hunting cartridge too.

I have three 6.5x47 Lapua rifles, the heavy gun is showing promise as a solid performer out to 600m, I've not taken it further yet.

The Grendel is a great cartridge, but I tend to view it as a 300m cartridge for hunting. As we do not have AR15 type rifles the merits of the Grendel in a gas gun are wasted here. If you are building a Rem700 or similar action into a long range target rifle almost everyone will go for a larger cartridge - mostly the 6.5 Lapua, some 260 Remington, and then into the large 7mm like a 7mm-06, 280 Rem, 284 or a 7mm SAUM.

Some gents who work hard at true long ranges (800m+) favour the 338 Edge or an improved 375 SnipeTAC based on a locally made 416 case. Cartridges like the 338 Lapua and 416 Barret attract attention due to their use as 'sniper rounds'. Some states still permit the ownership of 50cal rifles, but they are damned expensive to run and buying consumables is difficult due to the low demand (and federal disapproval).

[stokesrj]

Adamjp,
I think you sell the 6.5 Creedmoor short due to lack of familiarity, probably driven by the economics of the tariff structures. I understand your point about the brass and if Lapua brass was cheaper than Hornady brass in the US it might cause me to reconsider, but it isn't, here the Hornady is much cheaper. I own a 6.5X47, 6.5 Creedmoor, .260 Remington, 6.5X55 and many other 6.5 caliber rifles. I'm a competitor in High Power Rifle competition here in the US, both across the course, mid range and long range. I like the 6.5 Creedmoor better than the 6.5X47 and so do most high power competitors. It is easier to load for, operates at lower pressures and higher velocities than the 6.5X47 and you can buy factory ammunition capable of beating the 6.5X47 Lapua factory loads at less than half the price.

There isn't that much difference but the 6.5 Creedmoor is more favorably viewed here, at least in the competitive circles I travel in. This year I'm campaigning neither, having moved to the 6mm Hagar in which I also use Hornady brass, so far I've shot higher scores with it than either my 6.5 Creedmoor or 6.5X47 using the 105 Grain Berger Hybrid at 600 yards and beyond, I've shot a few perfect scores of 200 out of 200 using it. The Hagar is based on the .25 Remington case common also to the 6.8 SPC but longer and I shoot it out of an AR. You may be pleased to know I use almost exclusively Australian powders.
Bob

[bwaites]

I shot 2 different 6.5 Creedmoors a few weeks ago at Boomershoot, and both were lasers using Hornady brass and a couple different bullets. First shot hit on an 8" flag target at 700 yards, having never fired the rifle before in twitchy winds.

If the 6.5x47 shoots better I don't know how its possible!

My 7mm WSM shooting 168 and 180 Bergers is a smoking hot round also, but the 6.5's have a lot less recoil and shoot very flat. The RSAUM is essentially a dead cartridge in the US, with only a very few factory loads, and seldom available in the stores. WSM is still available, and has become the dominant long range competition round where allowed.

[XcountryRider]

If memory serves, Jay Guthrie's article in Shooting Times a few months ago did some comparisons of Grendel and 308. Good reading.

http://www.shootingtimes.com/2012/11/16/6-5mm-grendel-the-round-the-military-ought-to-have/

[adamjp]

The RSAUM is essentially a dead cartridge in the US, with only a very few factory loads, and seldom available in the stores. WSM is still available, and has become the dominant long range competition round where allowed.

I doubt there is any RSAUM factory ammunition in Australia! Defintiely never a popular cartridge, but it is preferred over the WSM when people consider it. Most go to a 280 AI, 7mm-06 or 284 Winchester though and use Lapua brass. 7mm RSAUM cases from Remington were $100+ per bag of 50 last time I looked. I'd love to be able to access the brass prices available through the big US chains.

I doubt that there is any noticeable difference between the 6.5x47 Lapua case and the 6.5 Creedmoor (6.5x48mm) case when it comes to pressure. The reality is that there is maybe 5gn of H2O between their capacities, and both cases were designed to operate at pressures beyond the 308 case, upwards to 62k PSI. To me there is little or nothing in it except that the Lapua case has a small rifle primer and allegedly has a slightly stiffer web. If you can spot a performance difference between the two of them in the same configuration I would be surprised. One inch of barrel, or even a 'fast' v 'slow' barrel will make more difference.

Since the Lapua brass is readily available, and cheaper than the Hornady brass for the Creedmoor (better quality too) it remains a no-brainer when you go to build a light long ranger here in Australia.